<?php
class RM_HSBC_Codes {

    function  convert($code = "GBP") {

        switch ($code) {
            case 'USD':
                return "840";
                break;
            case 'GBP':
                return "826";
                break;
            case 'EUR':
                return "978";
                break;
        }

        return false; // false if no match
    }
}